1. Technical Field
The present invention relates to a headlight control device with which a situation ahead of a vehicle is detected and a light distribution pattern is automatically switched, and particularly relates to a headlight control device capable of identifying reflected light of a headlight of the vehicle from other light sources.
2. Related Art
A headlight of a vehicle such as an automobile is generally capable of switching between driving beam (high beam) and passing beam (low beam) or capable of turning off a driving beam independently from a passing beam.
In recent years, there have been proposals for a function (auto high beam function) of recognizing a situation ahead of a vehicle with a camera, radar, or the like to automatically switch from high beam to low beam in the case where a vehicle ahead such as an oncoming car or preceding for which glare may become a problem is detected.
As a conventional technique relating to such an auto high beam, Japanese Unexamined Patent Application Publication No. 2011-255826, for instance, discloses a vehicle headlight that performs switching between a light distribution pattern for high beam and a light distribution pattern for low beam upon detection of a vehicle ahead with an onboard camera or the like, such that a light distribution pattern for low beam is selected regardless of the presence or absence of detection of a vehicle ahead while driving through a sharp curve where an oncoming car may approach from outside an angle of view (a blind angle) of the camera or the like, so that glare for an oncoming car is prevented when an oncoming car detection is unsuccessful.
In the case of performing auto high beam control, it is important to identify a light source of a vehicle ahead with high precision.
As a conventional technique relating to such light source identification, Japanese Patent No. 3660877, for instance, discloses that whether a light source is a moving light source or a static light source is identified and reflected in auto high beam control.
Conventionally, there have been cases where light for illumination from a headlight of a vehicle that is reflected by a reflector provided near a road is falsely recognized as a light source of another vehicle upon identification of a light source.
In the case where such reflected light has been falsely recognized as a vehicle ahead and switching from high beam to low beam has been performed, the visibility for a driver of the vehicle is reduced.
When a light source of a vehicle ahead is falsely recognized as reflected light of the headlight of the vehicle, glare may be caused by direct illumination of the vehicle ahead with a high beam.